Although the history of life is always in the past, there are many ways
we can look at present-day organisms, as well as recent history, to better
understand what has occurred through deep time. Artificial selection in
agriculture or laboratories provides a model for natural selection. Looking
at interactions of organisms in ecosystems helps us to understand how
populations adapt over time. Experiments demonstrate selection and adaptive
advantage. And we can see nested hierarchies in taxonomies based on common
descent.